| 序号 | 题目：3,4,5,7 | |
|---|---|---|
| 1 | ((4 × 3) + 7) + 5 | |
| 2 | ((7 + 5) − 4) × 3 | |
| 3 | ((5 × 4) + 7) − 3 | |
| 4 | ((4 × 3) + 5) + 7 | |
| 5 | ((5 × 4) − 3) + 7 | |
| 6 | (4 × 3) + (7 + 5) | |
| 7 | (5 × (7 − 3)) + 4 | |
| 8 | (5 × 4) + (7 − 3) | |
| 9 | (4 × (7 − 5)) × 3 | |
| 10 | (5 + 3) × (7 − 4) | |
| 11 | (5 + (7 − 4)) × 3 | |
| 12 | (4 × 3) × (7 − 5) | |
| 13 | (7 + (5 − 4)) × 3 | |
| 14 | (3 × (7 − 5)) × 4 | |
| 15 | (7 + 5) + (4 × 3) | |